The invention relates to a method and an arrangement for operating a fuel supply system of an internal combustion engine, especially of a motor vehicle. In the fuel supply system, fuel is pumped into a storage space with the aid of a pump and a pressure is generated in the storage space. In the fuel supply system, an actual value of the pressure is measured with the aid of a pressure sensor and the pressure in the storage space is controlled (open loop and/or closed loop) to a desired value. A fault in the fuel supply system is detected with a plausibility control.
U.S. Pat. No. 5,241,933 discloses a fuel supply system wherein the fuel pressure is controlled with the aid of a pressure controller and wherein a fault detecting device detects a fault in the fuel supply system and this fault is displayed with the aid of a display device. For this purpose, a difference pressure is formed from an actual pressure and a desired pressure. A corrective value is then determined from the difference pressure and the desired value of the pressure is corrected with the corrective value.
The corrective value is additionally supplied to a fault detection device wherein a check is made as to whether the corrective value lies within a permissible pressure range formed by two predetermined values. If the corrective value lies outside of this range, then a fault in the fuel supply system is detected and displayed.
The present invention has the task of improving a method of the species type in such a manner that the component, which causes the fault in the fuel supply system, can be determined.
The especially significant advantage of the present invention is that a precise diagnosis of the fuel supply system is achieved without additional components.